The objectives of the proposed research are a) to detect antigens of anaerobic organisms in the serum, urine, and exudates of diabetic patients infected with these organisms, by the methods of counterimmunoelectrophoresis and enzyme-linked immunosorbent assay (ELISA), as a means of early recognition of potentially lethal infections; b) to refine the techniques we have developed for the detection of antibodies against anaerobic organisms by Ouchterlony plate and IgG and IgM ELISa; and utilize these techniques to survey a large population of diabetic patients for antibodies against anaerobic organisms; and correlate the presence of detectable antibodies with the presence of clinical syndromes compatible with anaerobic infections in diabetics; c) to utilize polyethylene chambers implanted subcutaneously in rabbits, as a site for the production of model of monomicrobic anaerobic and mixed anaerobic and aerobic-anaerobic infection in order to correlate the timed sequence of the detection of antigens and antibodies with the development of early and progressive tissue destruction.